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Title: Micro-jets in confined turbulent cross flow

Abstract

The mixing of sub-millimetre diameter jets issuing into a turbulent cross flow is examined with a combination of laser diagnostic techniques. The cross flow stream is in a confined duct and the micro-jet issue from the sides of injector vanes. A range of cross jet momentum ratios, cross flow temperatures and turbulence intensities are investigated to examine the influence on the jet mixing. Methane, seeded with acetone, was used to measure the concentrations of the jets and the mixing of the jet fluid in the duct. Unlike previous jet in cross flow work, mixing appears to be dominated by the free stream turbulence, rather than the cross jet momentum ratios. Temperature increases in the free stream appear to increase the rate of mixing in the duct, despite the associated decrease in the Reynolds number. The dominance of the free stream turbulence in controlling the mixing is of particular interest in respect of gas turbine injection systems, as the cross jet momentum ratio is insufficient in defining the mixing process. (author)

Authors:
;  [1];  [2]
  1. School of Engineering, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom)
  2. Rolls-Royce plc, Combustion systems, Moor Lane, Derby DE24 8BJ (United Kingdom)
Publication Date:
OSTI Identifier:
20711981
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 30; Journal Issue: 4; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; GAS TURBINE POWER PLANTS; TURBULENT FLOW; JETS; MIXING; TEMPERATURE DEPENDENCE; REYNOLDS NUMBER; GAS INJECTION

Citation Formats

Kelman, J.B., Greenhalgh, D.A., and Whiteman, M. Micro-jets in confined turbulent cross flow. United States: N. p., 2006. Web. doi:10.1016/j.expthermflusci.2005.07.006.
Kelman, J.B., Greenhalgh, D.A., & Whiteman, M. Micro-jets in confined turbulent cross flow. United States. doi:10.1016/j.expthermflusci.2005.07.006.
Kelman, J.B., Greenhalgh, D.A., and Whiteman, M. Wed . "Micro-jets in confined turbulent cross flow". United States. doi:10.1016/j.expthermflusci.2005.07.006.
@article{osti_20711981,
title = {Micro-jets in confined turbulent cross flow},
author = {Kelman, J.B. and Greenhalgh, D.A. and Whiteman, M.},
abstractNote = {The mixing of sub-millimetre diameter jets issuing into a turbulent cross flow is examined with a combination of laser diagnostic techniques. The cross flow stream is in a confined duct and the micro-jet issue from the sides of injector vanes. A range of cross jet momentum ratios, cross flow temperatures and turbulence intensities are investigated to examine the influence on the jet mixing. Methane, seeded with acetone, was used to measure the concentrations of the jets and the mixing of the jet fluid in the duct. Unlike previous jet in cross flow work, mixing appears to be dominated by the free stream turbulence, rather than the cross jet momentum ratios. Temperature increases in the free stream appear to increase the rate of mixing in the duct, despite the associated decrease in the Reynolds number. The dominance of the free stream turbulence in controlling the mixing is of particular interest in respect of gas turbine injection systems, as the cross jet momentum ratio is insufficient in defining the mixing process. (author)},
doi = {10.1016/j.expthermflusci.2005.07.006},
journal = {Experimental Thermal and Fluid Science},
number = 4,
volume = 30,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}
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